For certain types of media items, such as envelopes, in order to load a volume of media items into a feed tray, the material is shingled. In this mode, the media items are stacked on edge in a feed tray and fed from the tray into the feeder. Control of stack force in shingle mode feeding is critical to the successful function of the feeder.
To provide stack forces on the shingled media item, the angle of the feed tray with respect to a feeder has been varied, as has the weight of a moveable sled provided to urge the shingled media items toward the feeder. The weight of the shingle feed tray sled, which may be adjusted by the sled design and the inclusion of dead weights, can create a slide hammer effect. This is a situation where the sled, for example, during handling of a feed tray when loading media items into the tray or connecting the tray to a feeder, can quickly slide from one end of the shingle feed tray to the other, striking the sled stops.
Feeders have utilized shingle feed trays mounted to the feeder with various tray angles such as between 22 and 25 degrees, to facilitate movement of the media items from the feed tray into the feeder. Arrangements of this type are employed in Pitney Bowes Inc. of Stamford, Conn., inserter products, such as the Pitney Bowes DI350, DI400, DI500, DI600, DI800 and console inserter systems. At such angles, most shingled media items readily slide down the feed tray guided by the side guides of the tray. However, the stack force against the feeder nudger separator system to singulate shingled media items from the stack of media items in the feed tray becomes a strong function of the amount of shingled media items in the feed tray.
The reliable performance of the feeder in singulating the shingled media items becomes impacted by the amount of shingled media items in the feed tray pressing against the current media item to be singulated. Treatments have been added to the surface of the side guides of shingle feed trays to regulate the friction between the shingled media items and the side guides. These treatments are implemented in efforts to increase reliable movement of the shingled media item stack toward the exit area of the feed tray and the feeding and singulation of the media item at the feed tray exit area. Side Guide treatments have included tapes, Teflon paints, oils, and plastic shims. Side Guide treatments of this type have been employed in products such as the Pitney Bowes DI350, DI400, DI500, DI600, DI800 and console inserter systems.